This invention relates generally to an insulated gate field effect device and to a method for its fabrication, and more specifically to an insulated gate field effect device having horizontal and vertical channel components and to a method for fabricating such a device.
The trend in insulated gate field effect devices is to reduce the size of device features in order to build smaller and smaller integrated circuits using those devices. As device features, and especially the channel length of insulated gate field effect transistors (IGFETS) are reduced, a number of problems are encountered. These include, for example, the problem of patterning the small device features using conventional optical lithography. Additionally, device problems such as hot carrier injection and drain induced barrier lowering are encountered. These and other similar problems present obstacles to the goal of manufacturing inexpensive and yet reliable, high density, small geometry insulated gate field effect circuits.
Accordingly, a need existed for an improved device structure and for a method of fabrication which would overcome the problems of prior art structures and which would allow the fabrication of small, highly integrated devices without resort to unconventional lithography techniques.
It is therefore an object of this invention to provide an improved and reliable short channel insulated gate field effect transistor.
It is further object of this invention to provide an improved insulated gate field effect device having a mix of short channel devices and conventional devices.
It is a still further object of this invention to provide an improved process for fabricating insulated gate field effect devices.